Method for eliminating disturbances in receiving wireless telegraphy and telephony



Jfine 1- A. MEISSNER 1.809.334

' METHOD FOR ELIMINATING DISTURBANCES IN.RECEIVING WIRELESS TELEGRAPHY AND TELEPHONY Filed F8! 19, 1924 avwwwoz ALEXANDER MnssNER @511 \MS/ E i km 1 METHOD OR ELIMVINATING 'which, by modulating aradio e uenc omr lation bymeans of low or medium frequency 7 Application filed 'fielarua ry 19, 1324; Serial .Nb."

: The invention relates 'to'fanjarrangement at a very go'odlefliciency, can generate a frelquency slightly different from the -origin1a1-" frequencyand so improve the ireless receive in b eliminating disturbances cau by?! otherowireless stations or atmospheric'sg This frequencies are weakened or fully annulled so 1 that they do not actup'onfthe receiving.:appa-' I .bodiment of my'invent'ion and frequency in such away that the disturbing ratus. I p I v V Theinvention will best'be understood 'from the following detaileddescription when read I in connectionwiththe drawings in which ke. a y I ing; circuit: E, is produced in the ojscillato --;*ci 1 cuit.I,'Whenthej Fig. 1 represents diagrammatically one em- Fig; 2 illustrates" 'dagrammal'ically at 1 V 1other,modificationthereof.-v g

I The principle of the inyention,-is., that the incoming radio frequency and the disturb of 20,000icycles, that: the note 3,-0.00is audibl'ein-the telphoneTZ 1 which fcl'e aim isreached'by modulating the receiving .-:5 c N radlo frequency .oscillatiom Which,'ifor in stance, can-be generated by a small heterodyn ilng' circuit; auxiliary "cathm'ie; value genera tor) acts uponcoiljL- I Exactly-"asin1the:c'on{ ect qnlo igureil ai ro gl; l v p db 693,783,- and in Germany Fhruary '24, 192

Figure 2 shows:anotherjex'ample of the i] yention; Coilglig is not supplied:byi'aIL'aiml'ha-ry {generatorbut the receiving .c 'rrent ;.arej,- 1 ead transformed into:;a:udi eque ing frequ'ency'aremodulated so-that an 'algf 1 Q tered radio frequency'i's ledt th r c y i system.

Figure l showsan exam ple of'suchacoh nection ill-Which twol'vacuum valves V and v V connectedzaccording to the balancing" method, areused; Theincoming radio freupon the gridsof thetwojyalves and- V connected according to the balancing methodfl e m Sense des;'a m l auxilia yi "tuned circuit coupled tofsa'i'd output cimuit generator of a frequency of; 3,000 cycles ifor instance,"acts in theoppos'ite.senseiacross-coil *L ruponthegrids ofvl and Viby 'woiikingioirf the not straight parts of theoharacteristics of the two Valves Va andV ltf'caifbeattaliirlled bf proper ea justment ,0 1 tie: Woi" 'hgf a. I c ph ints-of the Valye's'that onl o e f'thegtwogd frequency 1 modulated frequencies, either 17,000 or 23,000 cycles, is strongly developed-in the tuned os-i quehey, for instance, thatof the aerial A orof I} any other receiving system, "which may be 20,000 cycles, acts, upon coil L 'As -the schematic diagram shows, this'frequency acts -the Way known byimeans of'a-hetemdyning circuit'U which is for in'stancetunedfto the-r ;1"-

. generate-r1 circuit coupled to said .jampl fier 1 input,

1;,Said last named tuned {circuit ,b ei g-escil1acio o f thefsamefrequency; received frequency; adaptedz t'o l pr ducea'heat consistsl'in nc mi g' high treats iirequency oscillations, select-ivelyamplifyinv.'

e yairejapl s'hapullkamp a receiying lif r'equ input andfanf output circuit;

fi ha g-ten named input" circuit; a local audio 7 frequency hush said arrangement' being adapted to f combine said receiying "frequency" 'ahdQ Said locally generated frequency; a

and heterodyne" detection "means coupled 5t and using- E' Ql-alltd said llooallyf generg" method l 'quencyr waves with-locally generated audioj o n -0 e r l' an composite Wares oohininggthe valllrl-p'lified compositejyvayeWith a? w r q al; n frequ ys m ommeilfl 1 ,hi h frequency waves and detecting'the re- I i 3. In combinat ona pair of space discharge '2 fi, I 1,809,134 7" su tantwave. Y

devices arranged, to substantially form a quency in unlike sense on the inputelements push-puliicircuit having an i'nputcircuit and .an output circuit, means in said input" eirg v V acuit forfsilnultaneously impressing oscillau ftions of a desired frequency in like sense on' I the inputfelements of both said space dis charge devices, meansinsaid input for impressingosciilations of another desired fre- V of both said space discharge devices, said first named circuit actingto combine said twofree' .1 "quencies and produce resultant beat frequen- 'CIBS ln said output, means for-filtering out one of the "beat frequencies, means-for'comi- ,bining the filte'redbeat frequency withanotherfreque'ncyequal'to the frequency of one of'said firsttwo mentioned frequencies and ,"means for detecting the resultant energy; s I 4 '4. Ina receiving system, a pair of space I I discharge devicesarranged so as to formsub- *stantiaiiy a push-pull circuit having input {and output circuits, means for collecting transmitted signal energy and impressing the collected energy in the-input of said push pullfiarran'gemeflntfso astoztfiect both said ispace-Idischargedevices in like sense, a 1oca1 oscillator coupled to said inputfor impress- 7 'ing oscillations of a desired frequency in each ,offsaid twospac e discharge devices in un-] @likesensd'said 'twospace discharge devices acting to} combine the incoming frequency with thelocallygenerated frequency so, as

p te-produce beat notes in the outputcircuit oftysaid v',I ush-pu11, arrangement, a circuit 2 itun'ed to one of the beat note frequencies pro ;,,diiced-coup1e'd to said output circuitfand. a

detecting circuit couple'dfto said last named QciircuitV-Vand means for impressing onsaid p ;'jftunedcircuit'energy ofafrequencyequal to v 'j'i'the' in'coniing frequency.

- ALEXAN nii'Mmss R. 1 

